The invention relates to a DC voltage conversion device comprising:                first conversion means to receive the DC voltage and to supply a primary pulsed voltage, and        transformation means connected to the first means to supply a secondary pulsed voltage.        
The invention also relates to a converter for converting a DC voltage into AC voltage comprising:                the previously described DC voltage conversion device,        filtering means connected to said conversion device, and        second conversion means connected to the filtering means.        
The invention further relates to an uninterruptible electric power supply comprising:                storing means for storing electric power, and        a converter for converting a DC voltage into AC voltage connected to the storing means, said converter comprising the previously described DC voltage conversion device.        